Rediscovering Spinosaurus: First Semiaquatic Dinosaur

University of Chicago paleontologist Paul Sereno describes Spinosaurus aegyptiacus, a predator of the Cretaceous Period that had adapted to life in water 95 million years ago. Sereno, his UChicago colleague Nizar Ibrahim, and an international team of associates announced their discovery in the journal Science online, at the Science Express website, on 11 September.